Don't do it. That's what friends of Jerome Kern and Oscar Hammerstein II advised, upon learning they planned to turn Edna Ferber's 1926 novel "Show Boat" into a musical. Its treatment of black life in the South, along with its portrayal of unhappy and mixed marriages, weren't exactly the stuff of stage dreams. It was destined to be a financial disaster, they clucked.

But, as the book "On With the Show" tells us, the collaborators ignored the naysayers, especially since they had the backing of Florenz Ziegfeld, king of the musical stage in the years after World War I. "We had fallen in love with it," Hammerstein said of the material. "We couldn't keep our hands off it. We acted out scenes together and planned the actual direction. We sang to each other. We had ourselves swooning."

They took tryouts of "Show Boat" to Washington, Pittsburgh (it played the old Nixon Theater for a week in November), Cleveland and Philadelphia before its Dec. 27, 1927, opening at the Ziegfeld Theater in New York. Writing about it in The New York Times, critic Brooks Atkinson said it was "one of those epochal works about which garrulous old men gabble for 25 years after the scenery has rattled off to the storehouse."

The elaborate scenery for "Show Boat" didn't spend much time in the warehouse.

The original production ran until May 1929, making it the second longest-running musical of the decade. It wasn't that "Show Boat" lacked for competition; the night before its New York premiere, 11 productions opened on Broadway. At one point it was so popular that Ziegfeld made plans for a second New York production, although he later abandoned that idea.

"Show Boat," which spans the period from the 1880s to the Roaring '20s, tells the story of a floating theater called the Cotton Blossom and the performers who inhabit it or, to their heartbreak, are banished from it.

Presiding over the boat are Cap'n Andy Hawks and his wife, Parthy. Their innocent daughter, Magnolia, falls in love with Gaylord Ravenal, a dashing riverboat gambler who joins the troupe as an actor. Innocence and gambling addictions never go out of style, but the fate of Julie LaVerne may seem positively quizzical - if not cruel and outdated - to modern audiences.

Julie, the show's leading lady who is happily married to the leading man, is the product of a mixed marriage. When a vengeful, rejected admirer tells the sheriff that Julie is married to a white man - a criminal offense in that state - Julie and her husband are forced to leave.

She resurfaces and sacrifices a job to give Magnolia, now abandoned by her husband, a break. Years later, Magnolia and Ravenal are reunited by their daughter, now a star in her own right.

So, just how has "Show Boat" managed to survive in a time when most theatergoers want to flock to musicals such as "Lion King" with its dazzling choreography and movie source material?

Throw into the mix 500 props, a revolving door retrieved from the Bank of Scotland, a 1902 Dewit Motor Car, a 1927 custom roadster and four turn-of-the-century wagons and carriages.

Director Harold Prince reminds us that "Show Boat" is not just another American musical but the first great contemporary modern musical. "The first to merge the traditional, happy-go-lucky naivete of Broadway musical comedy with serious themes. The first with a score ranging from light-hearted, popular 32-bar songs to 19th-century operetta and grand opera."

Tom Bosley, playing Cap'n Andy in the production coming to Pittsburgh, says the music and the play's lineage are the keys to its longevity.

"Certain operas live forever. Certain paintings live forever. When you're dealing with a combination of great talents such as Florenz Ziegfeld, who produced the original, and of course Jerome Kern and Oscar Hammerstein, from material created originally by Edna Ferber, that's really an all-star group of people to work with."

Bosley, a Broadway veteran best known to younger audiences as dad Howard Cunningham on "Happy Days," thinks Prince has elevated the show to a new level. "There were things in the original production that they had to shy away from. Integration in those days, putting black people on stage with white people was not a popular situation. It was first produced in 1927 - it's as old as I am - and not all the black ensemble were black people. It was like the old minstrel shows."

The question of race would continue to dog the show before its Toronto opening in fall 1993. "Throughout pre-production and rehearsal, I was committed to eliminate any inadvertent stereotype in the original material, dialogue which may seem 'Uncle Tom' today," Kern says in the show's production notes. "However, I was determined not to rewrite history.

"The fact that during the 45-year period depicted in our musical there were lynchings, imprisonment and forced labor of the blacks in the United States is irrefutable. Indeed, the United States still cannot hold its head high with regard to racism."

Prince can hold his head high, however, over "Show Boat." When the revival opened in New York in fall '94, writer Ethan Mordden echoed the comments of Atkinson. "It is three hours of tempest and sunshine. It is a national treasure and needs to be consulted every so often. It's time."

Tracking the timeline for "Show Boat" includes many key dates, in addition to its 1927 debut:

1928 - First performance of "Show Boat" given in London. Paul Robeson, Kern's original choice for Joe in New York, is celebrated in London. Robeson, who would be forever associated with the song "Ol' Man River," would later play the role in New York.

1929 - Universal Studios releases the first film version of the story starring Laura La Plante, Joseph Schildkraut, Helen Morgan, Jules Bledsoe and Tess Gardella.

1932 - "Show Boat" returns triumphantly to New York. Writer Ferber sees the revival and marvels: "When Robeson finished singing 'Ol' Man River,' the show stopped. He sang it again. The show stopped. They called him back again and again. Other actors came out and made motions and their lips moved, and the bravos of the audience drowned all other sounds."

1936 - Universal releases another movie adaptation, starring Charles Winninger as the Cap'n, Helen Morgan as Julie, Robeson as Joe and Irene Dunne as Magnolia. Kern and Hammerstein write three new songs for the film.

1946 - A revival opens at New York's Ziegfeld Theatre with the song "Nobody Else But Me," the last song Kern ever wrote.

1951 - A third film version of "Show Boat" arrives in theaters. This one, which is what you'll find when you go to the video store, stars Howard Keel as the gambler, Kathryn Grayson as Magnolia and Ava Gardner as Julie.

1966 - Lincoln Center mounts another New York revival with Barbara Cook as Magnolia, Constance Towers as Julie and Stephen Douglass as Ravenal.

1971 - Cleo Laine stars as Julie in a London revival that becomes the longest running production (910 performances) by the time it closes in September 1973.

1982 - Houston Grand Opera stages a major production, later seen on Broadway, incorporating newly discovered material from the Rodgers and Hammerstein warehouse. In this same year, the complete original orchestral score - including material dropped during the tryouts - is found in the Warner Bros. music storage warehouse, leading to a landmark 1988 EMI/Angel recording.

1989 - Opera North and the Royal Shakespeare Company stage a new production at the Grand Theatre, Leeds, subsequently seen at the Royal Shakespeare Theatre in Stratford-Upon-Avon.

1990 - West End producer Pola Jones, Stoll Moss and The Arts Council present the Opera North/RSC production for a season at the London Palladium, followed by a regional tour.

1994 - After a lengthy run in Toronto, "Show Boat" triumphantly returns to New York with Prince as director. The cast includes John McMartin, Elaine Stritch, Rebecca Luker, Mark Jacoby, Lonette McKee, Gretha Boston and Michel Bell.

1995 - "Show Boat" wins five Tonys for best revival of a musical, direction of a musical, choreography, costume design and performance by a featured actress (Gretha Boston) in a musical.